The Ultimate Electric Bicycle
It was a cycling crowd (I was in a bike shop, after all) and I'd uttered the phrase that must not be uttered. Eyeballs glanced around, seeking to know the whim of the group"--would anyone admit anything other than disdain? I uttered it again, "Seriously," I said. "What do you think of electric bicycles?"
The issue of purity was raised. "Well, they seem to defeat the purity of the bicycle," someone said. "They're ugly as sin," another added.
Ugly and impure. But not, I imagined, in the outlaw biker kind of way. None of that so-bad-it's-good stuff here.
"So none of you are fans of of the electric bike?" I asked. A silence. Finally, from the back of the shop, someone said, "They might be okay if..." he carefully turned his words over before continuing. "Maybe if they got more people to stop driving cars so much." He looked around at his fellow cyclists, his knicker-wearing brethren, and they nodded their heads in modest approval. "I mean... I wouldn't buy one," he continued, the others shaking their heads in agreement with that too. "But they might be good for some people."
"Yeah, blind people," someone quipped.
Blind people indeed. The trouble with the electric bicycle, as that group was highly aware, is that they seem to have been designed by people who know nothing about bicycles, at least not good bicycles. The failure in design is not simply aesthetic, but functional as well. Introduced at the wrong time and marketed in the wrong way, the electric bike has suffered from a credibility problem induced by terrible design and poor performance. Among cyclists, electric bikes are thought of as slow, ugly, and poorly made. Among non-cyclists, they are thought of us fun little toys to be used in the confines of gated communities and destination resorts. But in spite of their image problems, electric bikes are beginning to emerge as a serious form of transportation. Thanks to advances in battery technology and a vibrant community of do-it-yourself enthusiasts, the electric bike category is poised for a transformation from stepchild, to glowing wunderkind of sustainable transportation. The purists will resist, naturally, but that's what purists do. The rest of us, we who desperately want an alternative to the automobile, will embrace the electric bicycle as soon as good ones become available
Larry Pizzi is a bike enthusiast with years in the bicycle business. And even though he's the public relations spokesman for Currie Technologies, the largest manufacturer of electric bikes in North America, he'll be the first to tell you that most electric bikes have been big failures.
"When electric bikes first came out," Pizzi says, "the technology just wasn't ready. We've seen dramatic improvements in all the technology. When Currie started, we had to develop everything: motors, controllers, none of it existed for an electric bike application. We even had to design our own battery charger. Seriously. No one made a charger. Now we don't have to do all the development work. There are other firms out there who have done a lot of the R&D so we don't have to do everything ourselves. It makes a huge difference in what's possible today versus previous offerings."
The biggest improvement has been in battery technology. The key to understanding the importance of batteries to the design of a lightweight, svelte, high-performing electric bicycle is energy density.
Energy density is a measure of how much energy can be stored for a given volume or weight. Early electric bicycles were powered by sealed lead acid (SLA) batteries, pretty much the same battery that powers the starter motor in your car. An SLA battery has an energy density of about 22 watt-hours per pound. To get a reasonable range and performance out of an electric bike, you'd need to have roughly 350 watt-hours of battery storage. With SLA batteries, that's a 20-pound battery. That means the battery would weigh as much as the whole bicycle. Nickel-Cadmium and Nickel-Metal-Hydride batteries were improvements over SLA, but even these have energy densities that fall shy of what is required, with the batteries weighing in at 12.8 and 8.5 pounds respectively.
But a new battery that packs the necessary punch is trickling into the market. Lithium batteries promise, and in fact have already delivered, 5-pound battery packs that store more than 350 watt-hours of energy. These small and powerful batteries have been around for a couple of years powering laptop computers, cellular phones, and, perhaps most famously, iPod music players. But now they're making their way into electric bike and car applications (the Tesla Roadster is the most hyped example of a lithium-powered EV.) But it remains to be seen if companies such as Currie, or any of the other electric bike manufacturers, can overcome that other failure of the past: poor design.
We now have the batteries and the suppliers of all the technology needed to make an electric bicycle that is useful as a means of transportation. But as of this writing, you can't walk into a bike shop and purchase an electric bike that can be repaired with standard bicycle components, that looks good (i.e., like a bicycle and not some kind of experiment in clichéd futuristic design,) and that performs well enough to commute with.
From a design standpoint, most electric bikes have been failures. And not just aesthetic failures but failures in performance as well. To understand why these bikes failed, we should probably take a step back and think about who these bikes were marketed toward.
When electric bikes first hit the North American market, the people responsible for them imagined that electric bikes would entice non-cyclists to throw a leg over the saddle. But that logic hit a big snag when, instead of buying electric bikes, people who had never had any interest in pedaling bought electric scooters instead. And having committed to gimmicky designs based on inferior bicycle components, these marketers found they had no product to lure people actually interested in cycling.
None of the early models could go much faster than fifteen miles per hour. It's not that these speeds are completely inadequate, it's just that most cyclists can achieve speeds of twenty-five miles per hour without any electric assist at all. Unless they're in great shape, they won't be able to maintain that speed for very long, but they do frequently go that fast on their own. In addition to their slow speeds, these bikes had poor ranges of 10-20 miles at best.
For a cyclist, the prospect of paying extra money and lugging around extra weight for a machine that won't even go as fast or as far as they can pedal is just not worth the trade-off. But because the first few waves of electric bicycles were never intended for use by cyclists, we ended up with ugly, slow machines that weren't much good for anything but zipping around retirement communities.
The focus on non-enthusiasts resulted not just in poor performance targets, but in poor aesthetic targets as well. When you're designing for a market uneducated about the intricacies of bicycle design, you can't rely on subtle indicators to sell product. A non-cyclist won't be impressed by a particular bottom bracket or headset. To lure that type of buyer you need cruder, more garish strokes; lots of plastic, bold new graphics, and design that screams "I'm an electric bike" are the kinds of features you go for.
There are already signs, however, that manufacturers are addressing these design failures. The technology now in place allows for enough flexibility in design to address past failures. And the market itself has changed.
The world of product design has undergone incredible changes over the past few years. The complete penetration of 3-D design software and rapid prototyping capability into the product development cycle, along with improved materials and manufacturing processes, has led to a cornucopia of products with superb design. Apple Computer has led the charge in this arena by filling the market with products that are well designed, well engineered, and superbly packaged. Post iPod, consumers expect nothing less than tasteful, well-appointed design.
What this means for the electric bike industry is a growing non-enthusiast market that is primed to appreciate the impeccable design of traditional bikes, a design that has reached a very refined state thanks to more than one hundred years of design evolution. Subtlety and tastefulness will become selling points.
Currie Technologies has developed a series of bikes they call the Izip Express. These bikes have higher top speeds and greater ranges than Currie's previous offerings. It remains to be seen, however, if their new offerings will appeal to cycling enthusiasts. The real test will be in the bike shops. If the bike shop employees dig your electric bike, chance are you've got something that a lot of other people will want as well.